qcodes.instrument_drivers.Keysight package

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.Infiniium.DSOFrequencyAxisParam(xorigin: float, xincrement: float, points: int, **kwargs: Any)[source]

Bases: Parameter

Frequency axis parameter for the Infiniium series DSO.

Initialize frequency axis. If values are unknown, they can be initialized to zero and filled in later.

get_raw() → ndarray[source]: Return the array corresponding to this time axis.

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.Infiniium.DSOTraceParam(name: str, instrument: Union[InfiniiumChannel, InfiniiumFunction], channel: str, **kwargs: Any)[source]

Bases: ParameterWithSetpoints

Trace parameter for the Infiniium series DSO

Initialize DSOTraceParam bound to a specific channel.

UNIT_MAP = {0: 'UNKNOWN', 1: 'V', 2: 's', 3: "''", 4: 'A', 5: 'dB'}

property setpoints: Sequence[Parameter]: Overwrite setpoint parameter to update setpoints if auto_digitize is true

property unit: str: Return the units for this measurement.

prepare_curvedata() → None[source]: Deprecated method to update waveform parameters.

update_setpoints(preamble: Optional[Sequence[str]] = None) → None[source]: Update waveform parameters. Must be called before data acquisition if instr.cache_setpoints is False

update_fft_setpoints() → None[source]: Update waveform parameters for an FFT.

get_raw() → ndarray[source]: Get waveform data from scope

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

validate(value: Any) → None

Overwrites the standard validate method to also check the the parameter has consistent shape with its setpoints. This only makes sense if the parameter has an Arrays validator

Arguments are passed to the super method

validate_consistent_shape() → None: Verifies that the shape of the Array Validator of the parameter is consistent with the Validator of the Setpoints. This requires that both the setpoints and the actual parameters have validators of type Arrays with a defined shape.

class qcodes.instrument_drivers.Keysight.Infiniium.AbstractMeasurementSubsystem(parent: InstrumentBase, name: str, **kwargs: Any)[source]

Bases: InstrumentModule

Submodule containing the measurement subsystem commands and associated parameters.

Note: these commands are executed on the waveform in the scope buffer. If you need to ensure a fresh value, run dso.digitize() prior to reading the measurement value.

Add parameters to measurement subsystem. Note: This should not be initialized directly, rather initialize BoundMeasurementSubsystem or UnboundMeasurementSubsystem.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.Infiniium.BoundMeasurement(parent: Union[InfiniiumChannel, InfiniiumFunction], name: str, **kwargs: Any)[source]

Bases: AbstractMeasurementSubsystem

Initialize measurement subsystem bound to a specific channel

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

log: InstrumentLoggerAdapter = get_instrument_logger(self, __name__)

metadata: Dict[str, Any] = {}

class qcodes.instrument_drivers.Keysight.Infiniium.UnboundMeasurement(parent: Infiniium, name: str, **kwargs: Any)[source]

Bases: AbstractMeasurementSubsystem

Initialize measurement subsystem where target is set by the parameter source.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

log: InstrumentLoggerAdapter = get_instrument_logger(self, __name__)

metadata: Dict[str, Any] = {}

class qcodes.instrument_drivers.Keysight.Infiniium.InfiniiumFunction(parent: Infiniium, name: str, channel: int, **kwargs: Any)[source]

Initialize an infiniium channel.

property channel: int

property channel_name: str

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.Infiniium.InfiniiumChannel(parent: Infiniium, name: str, channel: int, **kwargs: Any)[source]

Initialize an infiniium channel.

property channel: int

property channel_name: str

update_setpoints() → None[source]: Update time axis and offsets for this channel. Calling this function is required when instr.cache_setpoints is True whenever the scope parameters are changed.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.Infiniium.Infiniium(name: str, address: str, timeout: float = 20, channels: int = 4, silence_pyvisapy_warning: bool = False, **kwargs: Any)[source]

Bases: VisaInstrument

This is the QCoDeS driver for the Keysight Infiniium oscilloscopes

Initialises the oscilloscope.

Parameters

name – Name of the instrument used by QCoDeS
address – Instrument address as used by VISA
timeout – Visa timeout, in secs.
channels – The number of channels on the scope.
silence_pyvisapy_warning – Don’t warn about pyvisa-py at startup

run() → None[source]: Set the scope in run mode.

stop() → None[source]: Set the scope in stop mode.

single() → None[source]: Take a single acquisition

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

update_all_setpoints() → None[source]: Update the setpoints for all enabled channels. This method may be run at the beginning of a measurement rather than looping through each channel manually.

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

digitize(timeout: Optional[int] = None) → None[source]

Digitize a full waveform and block until the acquisition is complete.

Warning: If using pyvisa_py as your visa library, this will not work with acquisitions longer than a single timeout period. If you require long acquisitions either use Keysight/NI Visa or set timeout to be longer than the expected acquisition time.

qcodes.instrument_drivers.Keysight.KeysightAgilent_33XXX module

class qcodes.instrument_drivers.Keysight.KeysightAgilent_33XXX.OutputChannel(parent: Instrument, name: str, channum: int)[source]

Class to hold the output channel of a waveform generator

Parameters

parent – The instrument to which the channel is attached.
name – The name of the channel
channum – The number of the channel in question (1-2)

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.KeysightAgilent_33XXX.SyncChannel(parent: Instrument, name: str)[source]

Class to hold the sync output. Has very few parameters for single channel instruments

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.KeysightAgilent_33XXX.WaveformGenerator_33XXX(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: KeysightErrorQueueMixin, VisaInstrument

QCoDeS driver for the Keysight/Agilent 33XXX series of waveform generators

Parameters

name – The name of the instrument used internally by QCoDeS. Must be unique.
address – The VISA resource name.
silent – If True, no connect message is printed.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34410A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34410A_submodules.Keysight_34410A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34410A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34411A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34411A_submodules.Keysight_34411A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34411A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34460A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34460A_submodules.Keysight_34460A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34460A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34461A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34461A_submodules.Keysight_34461A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34461A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34465A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34465A_submodules.Keysight_34465A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34465A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_34470A_submodules module

class qcodes.instrument_drivers.Keysight.Keysight_34470A_submodules.Keysight_34470A(name: str, address: str, silent: bool = False, **kwargs: Any)[source]

Bases: _Keysight_344xxA

This is the qcodes driver for the Keysight 34470A Multimeter

Create an instance of the instrument.

Parameters

name – Name used by QCoDeS. Appears in the DataSet
address – Visa-resolvable instrument address.
silent – If True, the connect_message of the instrument is supressed. Default: False

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

abort_measurement() → None: Abort a measurement in progress, returning the instrument to the trigger idle state.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

autorange_once() → None

Performs immediate autorange and then turns autoranging off.

The value of the range parameter is also updated.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

decrease_range(range_value: Optional[float] = None, decrease_by: int = - 1) → None

Decrease the voltage range by a certain amount with default of -1. If limit is reached, the min range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
decrease_by – How much to decrease range by, default behavior is by a step of one.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

error() → Tuple[int, str]

Return the first error message in the queue. It also clears it from the error queue.

Up to 20 errors can be stored in the instrument’s error queue. Error retrieval is first-in-first-out (FIFO).

If more than 20 errors have occurred, the most recent error stored in the queue is replaced with -350,”Queue overflow”. No additional errors are stored until you remove errors from the queue. If no errors have occurred when you read the error queue, the instrument responds with +0,”No error”.

Returns: The error code and the error message.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

fetch() → ndarray

Waits for measurements to complete and copies all available measurements to the instrument’s output buffer. The readings remain in reading memory.

This query does not erase measurements from the reading memory. You can call this method multiple times to retrieve the same data.

Returns: a 1D numpy array of all measured values that are currently in the reading memory

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

flush_error_queue(verbose: bool = True) → None

Clear the instrument error queue, and prints it.

Parameters: verbose – If true, the error messages are printed. Default: True.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

increase_range(range_value: Optional[float] = None, increase_by: int = 1) → None

Increases the voltage range by a certain amount with default of 1. If limit is reached, the max range is used.

Parameters

range_value – The desired voltage range needed. Expressed by power of 10^x range from -3 to 10
increase_by – How much to increase range by, default behavior is by a step of one.

init_measurement() → None

Change the state of the triggering system from “idle” to “wait-for-trigger”, and clear the previous set of measurements from reading memory.

This method is an “overlapped” command. This means that after executing it, you can send other commands that do not affect the measurements.

Storing measurements in reading memory with this method is faster than sending measurements to the instrument’s output buffer using read method (“READ?” command) (provided you do not fetch, “FETCh?” command, until done).

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

read() → ndarray

Starts a new set of measurements, waits for all measurements to complete, and transfers all available measurements.

This method is similar to calling init_measurement() followed immediately by fetch().

Returns: a 1D numpy array of all measured values

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset() → None: Reset the instrument to factory defaults. Also updates the snapshot to reflect the new (default) values of parameters.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_B2962A module

class qcodes.instrument_drivers.Keysight.Keysight_B2962A.B2962AChannel(parent: Instrument, name: str, chan: int)[source]

Parameters

parent – The instrument to which the channel is attached.
name – The name of the channel
chan – The number of the channel in question (1-2)

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.Keysight_B2962A.B2962A(name: str, address: str, **kwargs: Any)[source]

Bases: VisaInstrument

This is the qcodes driver for the Keysight B2962A 6.5 Digit Low Noise Power Source

Status: alpha-version. .. todo:

- Implement any remaining parameters supported by the device
- Similar drivers have special handlers to map return values of
  9.9e+37 to inf, is this needed?

get_idn() → Dict[str, Optional[str]][source]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_N5173B module

class qcodes.instrument_drivers.Keysight.Keysight_N5173B.N5173B(name: str, address: str, **kwargs: Any)[source]

Bases: N5183B

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_N5183B module

class qcodes.instrument_drivers.Keysight.Keysight_N5183B.N5183B(name: str, address: str, **kwargs: Any)[source]

Bases: N51x1

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.Keysight_N6705B module

class qcodes.instrument_drivers.Keysight.Keysight_N6705B.N6705BChannel(parent: Instrument, name: str, chan: int)[source]

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.Keysight_N6705B.N6705B(name: str, address: str, **kwargs: Any)[source]

Bases: VisaInstrument

get_idn() → Dict[str, Optional[str]][source]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.KtM960x module

class qcodes.instrument_drivers.Keysight.KtM960x.Measure(name: str, instrument: KtM960x)[source]

Bases: MultiParameter

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

get_raw() → Tuple[Any, ...][source]: get_raw is called to perform the actual data acquisition from the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if get_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a get method on the parameter instance.

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

property full_names: tuple[str, ...]: Names of the parameter components including the name of the instrument and submodule that the parameter may be bound to. The name parts are separated by underscores, like this: instrument_submodule_parameter

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property setpoint_full_names: collections.abc.Sequence[collections.abc.Sequence[str]] | None: Full names of setpoints including instrument names, if available

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

property short_names: tuple[str, ...]

short_names is identical to names i.e. the names of the parameter parts but does not add the instrument name.

It exists for consistency with instruments and other parameters.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.KtM960x.KtM960x(name: str, address: str, options: str = '', dll_path: str = 'C:\\Program Files\\IVI Foundation\\IVI\\Bin\\KtM960x_64.dll', **kwargs: Any)[source]

Bases: Instrument

Provide a wrapper for the Keysight KtM960x DAC. This driver provides an interface into the IVI-C driver provided by Keysight. The .dll is installed by default into C:Program FilesIVI FoundationIVIBinKtM960x_64.dll but a different path can be supplied to the constructor

get_idn() → Dict[str, Optional[str]][source]: generates the *IDN dictionary for qcodes

get_errors() → Dict[int, str][source]

close() → None[source]

Irreversibly stop this instrument and free its resources.

Subclasses should override this if they have other specific resources to close.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low level method to write to the hardware and return a response.

Subclasses that define a new hardware communication should override this method. Subclasses that transform cmd should instead override ask.

Parameters: cmd – The string to send to the instrument.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low level method to write a command string to the hardware.

Subclasses that define a new hardware communication should override this method. Subclasses that transform cmd should instead override write.

Parameters: cmd – The string to send to the instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.KtM960xDefs module

qcodes.instrument_drivers.Keysight.KtMAwg module

class qcodes.instrument_drivers.Keysight.KtMAwg.KtMAWGChannel(parent: KtMAwg, name: str, chan: int)[source]

Represent the three channels of the Keysight KTM Awg driver. The channels can be independently controlled and programmed with seperate waveforms.

load_waveform(filename: str) → None[source]

clear_waveform() → None[source]

play_waveform() → None[source]

stop_waveform() → None[source]

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.KtMAwg.KtMAwg(name: str, address: str, options: str = '', dll_path: str = 'C:\\Program Files\\IVI Foundation\\IVI\\Bin\\KtMAwg_64.dll', **kwargs: Any)[source]

Bases: Instrument

AWG Driver for the Keysight M9336A PXIe I/Q Arbitrary Waveform Generator. This driver provides a simple wrapper around the IVI-C drivers from Keysight. The output configuration, gain can be controlled and a waveform can be loaded from a file.

get_idn() → Dict[str, Optional[str]][source]: generates the *IDN dictionary for qcodes

get_errors() → Dict[int, str][source]

close() → None[source]

Irreversibly stop this instrument and free its resources.

Subclasses should override this if they have other specific resources to close.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low level method to write to the hardware and return a response.

Subclasses that define a new hardware communication should override this method. Subclasses that transform cmd should instead override ask.

Parameters: cmd – The string to send to the instrument.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low level method to write a command string to the hardware.

Subclasses that define a new hardware communication should override this method. Subclasses that transform cmd should instead override write.

Parameters: cmd – The string to send to the instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.KtMAwgDefs module

qcodes.instrument_drivers.Keysight.N51x1 module

class qcodes.instrument_drivers.Keysight.N51x1.N51x1(name: str, address: str, min_power: int = - 144, max_power: int = 19, **kwargs: Any)[source]

Bases: VisaInstrument

This is the qcodes driver for Keysight/Agilent scalar RF sources. It has been tested with N5171B, N5181A, N5173B, N5183B

get_idn() → Dict[str, Optional[str]][source]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.N5222B module

class qcodes.instrument_drivers.Keysight.N5222B.N5222B(name: str, address: str, **kwargs: Any)[source]

Bases: PNABase

Driver for Keysight PNA N5222B.

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

averages_off() → None: Turn off trace averaging

averages_on() → None: Turn on trace averaging

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

get_options() → Sequence[str]

get_trace_catalog() → str

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset_averages() → None: Reset averaging

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

select_trace_by_name(trace_name: str) → int

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

property traces: ChannelList: Update channel list with active traces and return the new list

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.N5230C module

class qcodes.instrument_drivers.Keysight.N5230C.N5230C(name: str, address: str, **kwargs: Any)[source]

Bases: PNABase

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

averages_off() → None: Turn off trace averaging

averages_on() → None: Turn on trace averaging

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

get_options() → Sequence[str]

get_trace_catalog() → str

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset_averages() → None: Reset averaging

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

select_trace_by_name(trace_name: str) → int

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

property traces: ChannelList: Update channel list with active traces and return the new list

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.N5245A module

class qcodes.instrument_drivers.Keysight.N5245A.N5245A(name: str, address: str, **kwargs: Any)[source]

Bases: PNAxBase

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

averages_off() → None: Turn off trace averaging

averages_on() → None: Turn on trace averaging

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

get_options() → Sequence[str]

get_trace_catalog() → str

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset_averages() → None: Reset averaging

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

select_trace_by_name(trace_name: str) → int

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

property traces: ChannelList: Update channel list with active traces and return the new list

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.N52xx module

class qcodes.instrument_drivers.Keysight.N52xx.PNAAxisParameter(startparam: Parameter, stopparam: Parameter, pointsparam: Parameter, **kwargs: Any)[source]

Bases: Parameter

Axis parameter for traces from the PNA

get_raw() → ndarray[source]: Return the axis values, with values retrieved from the parent instrument

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.N52xx.PNALogAxisParamter(startparam: Parameter, stopparam: Parameter, pointsparam: Parameter, **kwargs: Any)[source]

Bases: PNAAxisParameter

Axis parameter for traces from the PNA

get_raw() → ndarray[source]: Return the axis values on a log scale, with values retrieved from the parent instrument

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.N52xx.PNATimeAxisParameter(startparam: Parameter, stopparam: Parameter, pointsparam: Parameter, **kwargs: Any)[source]

Bases: PNAAxisParameter

Axis parameter for traces from the PNA

get_raw() → ndarray[source]: Return the axis values on a time scale, with values retrieved from the parent instrument

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.N52xx.FormattedSweep(name: str, instrument: PNABase, sweep_format: str, label: str, unit: str, memory: bool = False, **kwargs: Any)[source]

Bases: ParameterWithSetpoints

Mag will run a sweep, including averaging, before returning data. As such, wait time in a loop is not needed.

property setpoints: Sequence[ParameterBase]: Overwrite setpoint parameter to ask the PNA what type of sweep

get_raw() → Sequence[float][source]: get_raw is called to perform the actual data acquisition from the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if get_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a get method on the parameter instance.

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Overwrites the standard validate method to also check the the parameter has consistent shape with its setpoints. This only makes sense if the parameter has an Arrays validator

Arguments are passed to the super method

validate_consistent_shape() → None: Verifies that the shape of the Array Validator of the parameter is consistent with the Validator of the Setpoints. This requires that both the setpoints and the actual parameters have validators of type Arrays with a defined shape.

class qcodes.instrument_drivers.Keysight.N52xx.PNAPort(parent: PNABase, name: str, port: int, min_power: Union[int, float], max_power: Union[int, float], **kwargs: Any)[source]

Allow operations on individual PNA ports. Note: This can be expanded to include a large number of extra parameters…

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.N52xx.PNATrace(parent: PNABase, name: str, trace_name: str, trace_num: int, **kwargs: Any)[source]

Allow operations on individual PNA traces.

run_sweep() → str[source]: Run a set of sweeps on the network analyzer. Note that this will run all traces on the current channel.

write(cmd: str) → None[source]: Select correct trace before querying

ask(cmd: str) → str[source]: Select correct trace before querying

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.N52xx.PNABase(name: str, address: str, min_freq: Union[int, float], max_freq: Union[int, float], min_power: Union[int, float], max_power: Union[int, float], nports: int, **kwargs: Any)[source]

Bases: VisaInstrument

Base qcodes driver for Agilent/Keysight series PNAs http://na.support.keysight.com/pna/help/latest/Programming/GP-IB_Command_Finder/SCPI_Command_Tree.htm

Note: Currently this driver only expects a single channel on the PNA. We: can handle multiple traces, but using traces across multiple channels may have unexpected results.

property traces: ChannelList: Update channel list with active traces and return the new list

get_options() → Sequence[str][source]

get_trace_catalog() → str[source]

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

select_trace_by_name(trace_name: str) → int[source]

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

reset_averages() → None[source]: Reset averaging

averages_on() → None[source]: Turn on trace averaging

averages_off() → None[source]: Turn off trace averaging

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.N52xx.PNAxBase(name: str, address: str, min_freq: Union[int, float], max_freq: Union[int, float], min_power: Union[int, float], max_power: Union[int, float], nports: int, **kwargs: Any)[source]

Bases: PNABase

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

averages_off() → None: Turn off trace averaging

averages_on() → None: Turn on trace averaging

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

get_options() → Sequence[str]

get_trace_catalog() → str

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset_averages() → None: Reset averaging

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

select_trace_by_name(trace_name: str) → int

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

property traces: ChannelList: Update channel list with active traces and return the new list

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visabackend: str = visabackend

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

visalib: str | None = visalib

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

log: InstrumentLoggerAdapter = get_instrument_logger(self, __name__)

metadata: Dict[str, Any] = {}

qcodes.instrument_drivers.Keysight.N9030B module

class qcodes.instrument_drivers.Keysight.N9030B.FrequencyAxis(start: Parameter, stop: Parameter, npts: Parameter, *args: Any, **kwargs: Any)[source]

Bases: Parameter

get_raw() → Any[source]: get_raw is called to perform the actual data acquisition from the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if get_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a get method on the parameter instance.

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.N9030B.Trace(number: int, *args: Any, **kwargs: Any)[source]

Bases: ParameterWithSetpoints

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

get_raw() → Any[source]: get_raw is called to perform the actual data acquisition from the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if get_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a get method on the parameter instance.

__getitem__(keys: Any) → SweepFixedValues: Slice a Parameter to get a SweepValues object to iterate over during a sweep

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

increment(value: Any) → None

Increment the parameter with a value

Parameters: value – Value to be added to the parameter.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property label: str: Label of the data used for plots etc.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

set_raw(value: Any) → None: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property setpoints: Sequence[ParameterBase]

Sequence of parameters to use as setpoints for this parameter.

Getter: Returns a list of parameters currently used for setpoints.
Setter: Sets the parameters to be used as setpoints from a sequence. The combined shape of the parameters supplied must be consistent with the data shape of the data returned from get on the parameter.

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

sweep(start: float, stop: float, step: Optional[float] = None, num: Optional[int] = None) → SweepFixedValues

Create a collection of parameter values to be iterated over. Requires start and stop and (step or num) The sign of step is not relevant.

Parameters

start – The starting value of the sequence.
stop – The end value of the sequence.
step – Spacing between values.
num – Number of values to generate.

Returns

Collection of parameter values to be iterated over.

Return type

Examples

>>> sweep(0, 10, num=5)
 [0.0, 2.5, 5.0, 7.5, 10.0]
>>> sweep(5, 10, step=1)
[5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
>>> sweep(15, 10.5, step=1.5)
>[15.0, 13.5, 12.0, 10.5]

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

property unit: str: The unit of measure. Use '' (the empty string) for unitless.

validate(value: Any) → None

Overwrites the standard validate method to also check the the parameter has consistent shape with its setpoints. This only makes sense if the parameter has an Arrays validator

Arguments are passed to the super method

validate_consistent_shape() → None: Verifies that the shape of the Array Validator of the parameter is consistent with the Validator of the Setpoints. This requires that both the setpoints and the actual parameters have validators of type Arrays with a defined shape.

class qcodes.instrument_drivers.Keysight.N9030B.SpectrumAnalyzerMode(parent: N9030B, name: str, *arg: Any, **kwargs: Any)[source]

Spectrum Analyzer Mode for Keysight N9030B instrument.

update_trace() → None[source]: Updates start and stop frequencies whenever span of/or center frequency is updated.

setup_swept_sa_sweep(start: float, stop: float, npts: int) → None[source]: Sets up the Swept SA measurement sweep for Spectrum Analyzer Mode.

autotune() → None[source]: Autotune quickly get to the most likely signal of interest, and position it optimally on the display.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.N9030B.PhaseNoiseMode(parent: N9030B, name: str, *arg: Any, **kwargs: Any)[source]

Phase Noise Mode for Keysight N9030B instrument.

setup_log_plot_sweep(start_offset: float, stop_offset: float, npts: int) → None[source]: Sets up the Log Plot measurement sweep for Phase Noise Mode.

autotune() → None[source]: On autotune, the measurement automatically searches for and tunes to the strongest signal in the full span of the analyzer.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.N9030B.N9030B(name: str, address: str, **kwargs: Any)[source]

Bases: VisaInstrument

Driver for Keysight N9030B PXA signal analyzer. Keysight N9030B PXA siganl analyzer is part of Keysight X-Series Multi-touch Signal Analyzers. This driver allows Swept SA measurements in Spectrum Analyzer mode and Log Plot measurements in Phase Noise mode of the instrument.

Parameters

name –
address –

reset() → None[source]: Reset the instrument by sending the RST command

abort() → None[source]: Aborts the measurement

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.P9374A module

class qcodes.instrument_drivers.Keysight.P9374A.P9374A(name: str, address: str, **kwargs: Any)[source]

Bases: PNAxBase

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

averages_off() → None: Turn off trace averaging

averages_on() → None: Turn on trace averaging

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

get_options() → Sequence[str]

get_trace_catalog() → str

Get the trace catalog, that is a list of trace and sweep types from the PNA.

The format of the returned trace is:: trace_name,trace_type,trace_name,trace_type…

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

reset_averages() → None: Reset averaging

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

select_trace_by_name(trace_name: str) → int

Select a trace on the PNA by name.

Returns: The trace number of the selected trace

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

property traces: ChannelList: Update channel list with active traces and return the new list

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visabackend: str = visabackend

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

visalib: str | None = visalib

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

log: InstrumentLoggerAdapter = get_instrument_logger(self, __name__)

metadata: Dict[str, Any] = {}

qcodes.instrument_drivers.Keysight.keysight_34934a module

class qcodes.instrument_drivers.Keysight.keysight_34934a.Keysight34934A(parent: Union[VisaInstrument, InstrumentChannel], name: str, slot: int)[source]

Bases: KeysightSwitchMatrixSubModule

Create an instance for module 34933A. :param parent: the system which the module is installed on :param name: user defined name for the module :param slot: the slot the module is installed

write(cmd: str) → None[source]: When the module is safety interlocked, users can not make any connections. There will be no effect when try to connect any channels.

validate_value(row: int, column: int) → None[source]

to check if the row and column number is within the range of the module layout.

Parameters

row – row value
column – column value

to_channel_list(paths: List[Tuple[int, int]], wiring_config: Optional[str] = '') → str[source]

convert the (row, column) pair to a 4-digit channel number ‘sxxx’, where s is the slot number, xxx is generated from the numbering function.

Parameters

paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]
wiring_config – for 1-wire matrices, values are ‘MH’, ‘ML’; for 2-wire matrices, values are ‘M1H’, ‘M2H’, ‘M1L’, ‘M2L’

Returns

in the format of ‘(@sxxx, sxxx, sxxx, sxxx)’, where sxxx is a 4-digit channel number

static get_numbering_function(rows: int, columns: int, wiring_config: Optional[str] = '') → Callable[[int, int], str][source]

to select the correct numbering function based on the matrix layout. On P168 of the user’s guide for Agilent 34934A High Density Matrix Module: http://literature.cdn.keysight.com/litweb/pdf/34980-90034.pdf there are eleven equations. This function here simplifies them to one.

Parameters

rows – the total row number of the matrix module
columns – the total column number of the matrix module
wiring_config – wiring configuration for 1 or 2 wired matrices

Returns

The numbering function to convert row and column in to a 3-digit number

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

are_closed(paths: List[Tuple[int, int]]) → List[bool]

to check if a list of channels is closed/connected

Parameters: paths – list of channels [(r1, c1), (r2, c2), (r3, c3)]
Returns: a list of True and/or False True if the channel is closed/connected False if it’s open/disconnected.

are_open(paths: List[Tuple[int, int]]) → List[bool]

to check if a list of channels is open/disconnected

Parameters: paths – list of channels [(r1, c1), (r2, c2), (r3, c3)]
Returns: a list of True and/or False True if the channel is closed/connected False if it’s open/disconnected.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

connect(row: int, column: int) → None

to connect/close the specified channels

Parameters

row – row number
column – column number

connect_paths(paths: List[Tuple[int, int]]) → None

to connect/close the specified channels.

Parameters: paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

disconnect(row: int, column: int) → None

to disconnect/open the specified channels

Parameters

row – row number
column – column number

disconnect_paths(paths: List[Tuple[int, int]]) → None

to disconnect/open the specified channels.

Parameters: paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

is_closed(row: int, column: int) → bool

to check if a channel is closed/connected

Parameters

row – row number
column – column number

Returns

True if the channel is closed/connected False if it’s open/disconnected.

is_open(row: int, column: int) → bool

to check if a channel is open/disconnected

Parameters

row – row number
column – column number

Returns

True if the channel is open/disconnected False if it’s closed/connected.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.keysight_34980a module

qcodes.instrument_drivers.Keysight.keysight_34980a.post_execution_status_poll(func: Callable[[...], T]) → Callable[[...], T][source]

Generates a decorator that clears the instrument’s status registers before executing the actual call and reads the status register after the function call to determine whether an error occurs.

Parameters: func – function to wrap

class qcodes.instrument_drivers.Keysight.keysight_34980a.Keysight34980A(name: str, address: str, terminator: str = '\n', **kwargs: Any)[source]

Bases: VisaInstrument

QCodes driver for 34980A switch/measure unit

Create an instance of the instrument.

Parameters

name – Name of the instrument instance
address – Visa-resolvable instrument address.

get_status() → int[source]

Queries status register

Returns: 0 if there is no error

get_error() → str[source]

Queries error queue

Returns: error message, or ‘+0,”No error”’ if there is no error

clear_status() → None[source]: Clears status register and error queue of the instrument.

reset() → None[source]: Performs an instrument reset. Does not reset error queue!

ask(cmd: str) → str[source]

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write(cmd: str) → None[source]

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

scan_slots() → None[source]: Scan the occupied slots and make an object for each switch matrix module installed

property system_slots_info: Dict[int, Dict[str, str]]

disconnect_all(slot: Optional[int] = None) → None[source]

to open/disconnect all connections on select module

Parameters: slot – slot number, between 1 and 8 (self._total_slot), default value is None, which means all slots

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.keysight_34980a_submodules module

class qcodes.instrument_drivers.Keysight.keysight_34980a_submodules.KeysightSubModule(parent: Union[VisaInstrument, InstrumentChannel], name: str, slot: int)[source]

A base class for submodules for the 34980A systems.

Parameters

parent – the system which the module is installed on
name – user defined name for the module
slot – the slot the module is installed

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.keysight_34980a_submodules.KeysightSwitchMatrixSubModule(parent: Union[VisaInstrument, InstrumentChannel], name: str, slot: int)[source]

Bases: KeysightSubModule

A base class for Switch Matrix submodules for the 34980A systems.

validate_value(row: int, column: int) → None[source]

to check if the row and column number is within the range of the module layout.

Parameters

row – row value
column – column value

to_channel_list(paths: List[Tuple[int, int]], wiring_config: Optional[str] = None) → str[source]

convert the (row, column) pair to a 4-digit channel number ‘sxxx’, where s is the slot number, xxx is generated from the numbering function. This may be different for different modules.

Parameters

paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]
wiring_config – for 1-wire matrices, values are ‘MH’, ‘ML’; for 2-wire matrices, values are ‘M1H’, ‘M2H’, ‘M1L’, ‘M2L’

Returns

in the format of ‘(@sxxx, sxxx, sxxx, sxxx)’, where sxxx is a 4-digit channel number

is_open(row: int, column: int) → bool[source]

to check if a channel is open/disconnected

Parameters

row – row number
column – column number

Returns

True if the channel is open/disconnected False if it’s closed/connected.

is_closed(row: int, column: int) → bool[source]

to check if a channel is closed/connected

Parameters

row – row number
column – column number

Returns

True if the channel is closed/connected False if it’s open/disconnected.

connect(row: int, column: int) → None[source]

to connect/close the specified channels

Parameters

row – row number
column – column number

disconnect(row: int, column: int) → None[source]

to disconnect/open the specified channels

Parameters

row – row number
column – column number

connect_paths(paths: List[Tuple[int, int]]) → None[source]

to connect/close the specified channels.

Parameters: paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]

disconnect_paths(paths: List[Tuple[int, int]]) → None[source]

to disconnect/open the specified channels.

Parameters: paths – list of channels to connect [(r1, c1), (r2, c2), (r3, c3)]

are_closed(paths: List[Tuple[int, int]]) → List[bool][source]

to check if a list of channels is closed/connected

Parameters: paths – list of channels [(r1, c1), (r2, c2), (r3, c3)]
Returns: a list of True and/or False True if the channel is closed/connected False if it’s open/disconnected.

are_open(paths: List[Tuple[int, int]]) → List[bool][source]

to check if a list of channels is open/disconnected

Parameters: paths – list of channels [(r1, c1), (r2, c2), (r3, c3)]
Returns: a list of True and/or False True if the channel is closed/connected False if it’s open/disconnected.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

log: InstrumentLoggerAdapter = get_instrument_logger(self, __name__)

metadata: Dict[str, Any] = {}

qcodes.instrument_drivers.Keysight.keysight_b220x module

qcodes.instrument_drivers.Keysight.keysight_b220x.post_execution_status_poll(func: Callable[[...], T]) → Callable[[...], T][source]

Generates a decorator that clears the instrument’s status registers before executing the actual call and reads the status register after the function call to determine whether an error occured.

Parameters: func – function to wrap

class qcodes.instrument_drivers.Keysight.keysight_b220x.KeysightB220X(name: str, address: str, **kwargs: Any)[source]

Bases: VisaInstrument

QCodes driver for B2200 / B2201 switch matrix

Note: The B2200 consists of up to 4 modules and provides two channel configuration modes, Normal and Auto. The configuration mode defines whether multiple switch modules are treated as one (Auto mode), or separately (Normal mode). This driver only implements the Auto mode. Please read the manual section on Channel Configuration Mode for more info.

connect(input_ch: int, output_ch: int) → None[source]

Connect given input/output pair.

Parameters

input_ch – Input channel number 1-14
output_ch – Output channel number 1-48

connect_paths(paths: Sequence[Tuple[int, int]]) → None[source]

disconnect_paths(paths: Sequence[Tuple[int, int]]) → None[source]

disconnect(input_ch: int, output_ch: int) → None[source]

Disconnect given Input/Output pair.

Parameters

input_ch – Input channel number 1-14
output_ch – Output channel number 1-48

disconnect_all() → None[source]

opens all connections.

If ground or bias mode is enabled it will connect all outputs to the GND or Bias Port

bias_disable_all_outputs() → None[source]: Removes all outputs from list of ports that will be connected to GND input if port is unused and bias mode is enabled.

bias_enable_all_outputs() → None[source]: Adds all outputs to list of ports that will be connected to bias input if port is unused and bias mode is enabled.

bias_enable_output(output: int) → None[source]

Adds output to list of ports that will be connected to bias input if port is unused and bias mode is enabled.

Parameters: output – int 1-48

bias_disable_output(output: int) → None[source]

Removes output from list of ports that will be connected to bias input if port is unused and bias mode is enabled.

Parameters: output – int 1-48

gnd_enable_output(output: int) → None[source]

Adds output to list of ports that will be connected to GND input if port is unused and bias mode is enabled.

Parameters: output – int 1-48

gnd_disable_output(output: int) → None[source]

Removes output from list of ports that will be connected to GND input if port is unused and bias mode is enabled.

Parameters: output – int 1-48

gnd_enable_all_outputs() → None[source]: Adds all outputs to list of ports that will be connected to GND input if port is unused and bias mode is enabled.

gnd_disable_all_outputs() → None[source]: Removes all outputs from list of ports that will be connected to GND input if port is unused and bias mode is enabled.

couple_port_autodetect() → None[source]

Autodetect Kelvin connections on Input ports

This will detect Kelvin connections on the input ports and enable couple mode for found kelvin connections. Kelvin connections must use input pairs that can be couple-enabled in order to be autodetected.

{(1, 2), (3, 4), (5, 6), (7, 8), (9, 10), (11, 12), (13, 14)}

Also refer to the manual for more information.

clear_status() → None[source]: Clears status register and error queue of the instrument.

reset() → None[source]

Performs an instrument reset.

Does not reset error queue!

static parse_channel_list(channel_list: str) → Set[Tuple[int, int]][source]: Generate a set of (input, output) tuples from a SCPI channel list string.

to_channel_list(paths: Sequence[Tuple[int, int]]) → str[source]

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters: cmd – The string to send to the instrument.
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters: cmd – The command to send to the instrument.

visa_handle: pyvisa.resources.MessageBasedResource = visa_handle: The VISA resource used by this instrument.

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.Keysight.keysight_e4980a module

class qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair(name: str, names: Sequence[str], units: Sequence[str], **kwargs: Any)[source]

Bases: MultiParameter

Data class for E4980A measurement, which will always return two items at once.

The two items are for two different parameters, depending on the measurement function. Hence, the names of the two attributes are created from the “names” tuple of the measurement functions.

Examples

To create a measurement data with capacitance=1.2, and dissipation_factor=3.4.

>>> data = MeasurementPair(name="CPD",
                            names=("capacitance", "dissipation_factor"),
                            units=("F", ""))
>>> data.set((1.2, 3.4))
>>> data.get()
(1.2, 3.4)

value: Tuple[float, float] = (0.0, 0.0)

set_raw(value: Tuple[float, float]) → None[source]: set_raw is called to perform the actual setting of a parameter on the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if set_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a set method on the parameter instance.

get_raw() → Tuple[Any, ...][source]: get_raw is called to perform the actual data acquisition from the instrument. This method should either be overwritten to perform the desired operation or alternatively for Parameter a suitable method is automatically generated if get_cmd is supplied to the parameter constructor. The method is automatically wrapped to provide a get method on the parameter instance.

__str__() → str: Include the instrument name with the Parameter name if possible.

property abstract: bool | None

property full_name: str: Name of the parameter including the name of the instrument and submodule that the parameter may be bound to. The names are separated by underscores, like this: instrument_submodule_parameter.

property full_names: tuple[str, ...]: Names of the parameter components including the name of the instrument and submodule that the parameter may be bound to. The name parts are separated by underscores, like this: instrument_submodule_parameter

get_ramp_values(value: float | collections.abc.Sized, step: Optional[float] = None) → Sequence[float | collections.abc.Sized]

Return values to sweep from current value to target value. This method can be overridden to have a custom sweep behaviour. It can even be overridden by a generator.

Parameters

value – target value
step – maximum step size

Returns

List of stepped values, including target value.

property gettable: bool: Is it allowed to call get on this parameter?

property instrument: InstrumentBase | None: Return the first instrument that this parameter is bound to. E.g if this is bound to a channel it will return the channel and not the instrument that the channel is bound too. Use root_instrument() to get the real instrument.

property inter_delay: float

Delay time between consecutive set operations. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay between sets.

Getter

Returns the current inter_delay.

Setter

Sets the value of the inter_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str: Name of the parameter. This is identical to short_name().

property name_parts: list[str]: List of the parts that make up the full name of this parameter

property post_delay: float

Delay time after start of set operation, for each set. The actual time will not be shorter than this, but may be longer if the underlying set call takes longer.

Typically used in conjunction with step to create an effective ramp rate, but can also be used without a step to enforce a delay after every set. One might think of post_delay as how long a set operation is supposed to take. For example, there might be an instrument that needs extra time after setting a parameter although the command for setting the parameter returns quickly.

Getter

Returns the current post_delay.

Setter

Sets the value of the post_delay.

Raises

TypeError – If delay is not int nor float
ValueError – If delay is negative

property raw_value: Any

Note that this property will be deprecated soon. Use cache.raw_value instead.

Represents the cached raw value of the parameter.

Getter: Returns the cached raw value of the parameter.

restore_at_exit(allow_changes: bool = True) → _SetParamContext

Use a context manager to restore the value of a parameter after a with block.

By default, the parameter value may be changed inside the block, but this can be prevented with allow_changes=False. This can be useful, for example, for debugging a complex measurement that unintentionally modifies a parameter.

Example

>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.restore_at_exit():
...     p.set(3)
...     print(f"value inside with block: {p.get()}")  # prints 3
>>> print(f"value after with block: {p.get()}")  # prints 2
>>> with p.restore_at_exit(allow_changes=False):
...     p.set(5)  # raises an exception

property root_instrument: InstrumentBase | None: Return the fundamental instrument that this parameter belongs too. E.g if the parameter is bound to a channel this will return the fundamental instrument that that channel belongs to. Use instrument() to get the channel.

set_to(value: Any, allow_changes: bool = False) → _SetParamContext

Use a context manager to temporarily set a parameter to a value. By default, the parameter value cannot be changed inside the context. This may be overridden with allow_changes=True.

Examples

>>> from qcodes.parameters import Parameter
>>> p = Parameter("p", set_cmd=None, get_cmd=None)
>>> p.set(2)
>>> with p.set_to(3):
...     print(f"p value in with block {p.get()}")  # prints 3
...     p.set(5)  # raises an exception
>>> print(f"p value outside with block {p.get()}")  # prints 2
>>> with p.set_to(3, allow_changes=True):
...     p.set(5)  # now this works
>>> print(f"value after second block: {p.get()}")  # still prints 2

property setpoint_full_names: collections.abc.Sequence[collections.abc.Sequence[str]] | None: Full names of setpoints including instrument names, if available

property settable: bool: Is it allowed to call set on this parameter?

property short_name: str: Short name of the parameter. This is without the name of the instrument or submodule that the parameter may be bound to. For full name refer to full_name().

property short_names: tuple[str, ...]

short_names is identical to names i.e. the names of the parameter parts but does not add the instrument name.

It exists for consistency with instruments and other parameters.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the parameter as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

If the parameter has been initiated with snapshot_value=False, the snapshot will NOT include the value and raw_value of the parameter.

Parameters

update – If True, update the state by calling parameter.get() unless snapshot_get of the parameter is False. If update is None, use the current value from the cache unless the cache is invalid. If False, never call parameter.get().
params_to_skip_update – No effect but may be passed from superclass

Returns

base snapshot

property snapshot_value: bool: If True the value of the parameter will be included in the snapshot.

property step: float | None

Stepsize that this Parameter uses during set operation. Stepsize must be a positive number or None. If step is a positive number, this is the maximum value change allowed in one hardware call, so a single set can result in many calls to the hardware if the starting value is far from the target. All but the final change will attempt to change by +/- step exactly. If step is None stepping will not be used.

Getter

Returns the current stepsize.

Setter

Sets the value of the step.

Raises

TypeError – if step is set to not numeric or None
ValueError – if step is set to negative
TypeError – if step is set to not integer or None for an integer parameter
TypeError – if step is set to not a number on None

property underlying_instrument: InstrumentBase | None

Returns an instance of the underlying hardware instrument that this parameter communicates with, per this parameter’s implementation.

This is useful in the case where a parameter does not belongs to an instrument instance that represents a real hardware instrument but actually uses a real hardware instrument in its implementation (e.g. via calls to one or more parameters of that real hardware instrument). This is also useful when a parameter does belong to an instrument instance but that instance does not represent the real hardware instrument that the parameter interacts with: hence root_instrument of the parameter cannot be the hardware_instrument, however underlying_instrument can be implemented to return the hardware_instrument.

By default it returns the root_instrument of the parameter.

validate(value: Any) → None

Validate the value supplied.

Parameters

value – value to validate

Raises

TypeError – If the value is of the wrong type.
ValueError – If the value is outside the bounds specified by the validator.

class qcodes.instrument_drivers.Keysight.keysight_e4980a.E4980AMeasurements[source]

Bases: object

All the measurement function for E4980A LCR meter. See user’s guide P353 https://literature.cdn.keysight.com/litweb/pdf/E4980-90230.pdf?id=789356

CPD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CPD at 139766794833008>

CPQ(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CPQ at 139766794836176>

CPG(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CPG at 139766794836224>

CPRP(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CPRP at 139766794833056>

CSD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CSD at 139766794840976>

CSQ(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CSQ at 139766794834640>

CSRS(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: CSRS at 139766794831472>

LPD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LPD at 139766794838864>

LPQ(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LPQ at 139766794845008>

LPG(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LPG at 139766794845392>

LPRP(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LPRP at 139766794845776>

LSD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LSD at 139766794846160>

LSQ(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LSQ at 139766794837280>

LSRS(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LSRS at 139766794832000>

LSRD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: LSRD at 139766794830416>

RX(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: RX at 139766794835600>

ZTD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: ZTD at 139766794837808>

ZTR(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: ZTR at 139766794832528>

GB(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: GB at 139766794842032>

YTD(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: YTD at 139766794843088>

YTR(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: YTR at 139766794844672>

VDID(*args: Any, **kwargs: Any) → Optional[Any] = <qcodes.instrument_drivers.Keysight.keysight_e4980a.MeasurementPair: VDID at 139766794842560>

class qcodes.instrument_drivers.Keysight.keysight_e4980a.Correction4980A(parent: VisaInstrument, name: str)[source]

Module for correction settings.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: InstrumentBase: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = False, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters: verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: dict[str, ParameterBase] = {}: All the parameters supported by this instrument. Usually populated via add_parameter().

functions: dict[str, Function] = {}: All the functions supported by this instrument. Usually populated via add_function().

submodules: dict[str, InstrumentModule | ChannelTuple] = {}: All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: dict[str, InstrumentModule] = {}: All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.Keysight.keysight_e4980a.KeysightE4980A(name: str, address: str, terminator: str = '\n', **kwargs: Any)[source]

Bases: VisaInstrument

QCodes driver for E4980A Precision LCR Meter

Create an instance of the instrument.

Parameters

name – Name of the instrument instance
address – Visa-resolvable instrument address.

property correction: Correction4980A

property measure_impedance: MeasurementPair

property measurement: MeasurementPair

__del__() → None: Close the instrument and remove its instance record.

__getitem__(key: str) → collections.abc.Callable[[...], Any] | qcodes.parameters.parameter.Parameter: Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None: Prevent pickling instruments, and give a nice error message.

__repr__() → str: Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only.

Note

We do not recommend the usage of Function for any new driver. Function does not add any significant features over a method defined on the class.

Parameters

name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.
**kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[type[qcodes.parameters.parameter_base.ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.
parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.
**kwargs – Constructor arguments for parameter_class.

Raises

KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.
ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: InstrumentModule | ChannelTuple) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

name – How the submodule will be stored within instrument.submodules and also how it can be addressed.
submodule – The submodule to be stored.

Raises

KeyError – If this instrument already contains a submodule with this name.
TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: list[qcodes.instrument.instrument_base.InstrumentBase]

Ancestors in the form of a list of InstrumentBase

The list starts with the current module then the parent and the parents parent until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters: cmd – The string to send to the instrument.
Returns: response
Raises: Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters: cmd – The command to send to the instrument.
Returns: The instrument’s response.
Return type: str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

func_name – The name of a function of this instrument.
*args – any arguments to the function.

Returns

The return value of the function.

close() → None: Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

idn_param – Name of parameter that returns ID dict. Default IDN.
begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']: A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []: A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None: Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[type[T]] = None) → T

Find an existing instrument by name.

Parameters

name – Name of the instrument.
instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

KeyError – If no instrument of that name was found, or if its reference is invalid (dead).
TypeError – If a specific class was requested but a different type was found.

property full_name: str

Full name of the instrument.

For an InstrumentModule this includes all parents separated by _

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters: param_name – The name of a parameter of this instrument.
Returns: The current value of the parameter.

get_idn() → dict[str, str | None]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns: A dict containing vendor, model, serial, and firmware.

classmethod instances() → list[qcodes.instrument.instrument.Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns: A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters: instr_instance – Instance of an Instrument class or its subclass.

property label: str: Nicely formatted label of the instrument.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters: metadata – Metadata to load.

property name: str

Full name of the instrument

This is equivalent to full_name() for backwards compatibility.

property name_parts: list[str]: A list of all the parts of the instrument name from root_instrument() to the current InstrumentModule.

omit_delegate_attrs: List[str] = []: A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase | None: The parent instrument. By default, this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.
max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters: instance – Instance to record.
Raises: KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters: instance – The instance to remove

property root_instrument: InstrumentBase

The topmost parent of this module.

For the root_instrument this is self.

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

param_name – The name of a parameter of this instrument.
value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters: address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: str | None) → None

Change the read terminator to use.

Parameters: terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

property short_name: str

Short name of the instrument.

For an InstrumentModule this does not include any parent names.

snapshot(update: Optional[bool] = False) → Dict[str, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters: update – Passed to snapshot_base.
Returns: Base snapshot.

snapshot_base(update: bool | None = True, params_to_skip_update: Optional[Sequence[str]] = None) → dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.
params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type